Frame element for supporting sinuous spring strips



March 1967 G. J. BIRGBAUER, JR 3,308,487

FRAME ELEMENT FOR SUPPORTING SINUOUS SPRING STRIPS Filed May 18, 1964 IN VEN TOR.

W?@- 5 KWZ %g 3,308,487 Patented Mar. 14, 1967 This invention relates toframe elements for supporting spring strips, particularly to a frameelement of Z-section having the web and flange lanced to providecollapsible tunnel for receiving the end of the spring strip.

Difliculties have been experienced heretofore in providing securingmeans for the end of spring strips to elements of a frame of chairs,davenports, beds and the like. otherwise secured to the wood members ofa frame or lanced fingers were provided in the metal frames over whichthe ends of the spring strips were secured.

The present invention pertains to the formation of a Z-shaped metalelement for the frame made from light sheet material with the metalalong one edge reversely bent upon itself to provide additional strengththereto. The web and the other arm of the element are lanced at spacedapart points therebetween with the material formed outwardly in theangle area between the web and arm to provide an elongated tunnel whichwill receive the supporting end of the sinuous spring strip.

The end is locked in position when the material forming the tunnel hasthe upper portion forced back into the plane of the web and with thelower portion encompassing the spring strip end. The are inherent incertain types of spring strips causes a crown to occur to the springstrips which form the seating area. The flange portion of the frameelement adjacent to the tunnels may be bent at an angle to force a crownin the spring strips when flat strips are employed.

The frame element provides an exceedingly light frame which hassufficient rigidity and ruggedness to support the ends of the sinuousspring strips which are securely locked thereon after the upper portionof the lanced metal is forced back into alignment with the web of theelement.

Accordingly, the main objects of the invention are: to provide a frameelement of angle section with lanced areas formed outwardly to providetunnels for the reception of the end of the sinuous spring strip whichis locked to the element when the tunnel portion has a section bent backinto the plane of the web of the element; to provide a frame element forsecuring the ends of the sinuous spring strips with a web and twooppositely extending flanges with the web and one flange lanced atspaced points with the metal therebetween forced outwardly to form anelongated tunnel which, for the end of the spring strip which is securedtherein, when a portion 7 of the lanced metal is moved into the plane ofthe element;

to provide a frame element of thin material having a central web and twooppositely extending flanges with elongated tunnel sections cut from theweb and one flange with the outer portion of the other flange reverselybent thereupon to add strength to the element, and in general, toprovide frame element for supporting the ends of spring strips which issimple in construction, and which securely locks the end of the springstrip thereto in the area between a flange and the web portion of theelement.

Other objects and features of novelty of the invention will bespecifically pointed out or will become apparent when referring, for abetter understanding of the invention, to the following descriptiontaken in conjunction with the accompanying drawings, wherein:

FIGURE 1 is a plan view of a frame element having a Separate clips havebeen used which are nailed or spring secured thereto in a mannerembodying features of the present invention;

FIG. 2 is a sectional view of the structure illustrated in FIGURE 1,taken on the line 22 thereof;

FIG. 3 is a perspective view of the structure illustrated in FIG. 2;

FIG. 4- is a view of the structure illustrated in FIG. 3 before thesinuous spring strip is secured thereto; and

FIG. 5 is a view of structure, similar to that illustrated in FIG. 2,showing another form of the invention.

The frame element of the present invention, employed in chairs,davenports, beds and the like, is made from a thin sheet of materialhaving a web 11, an inwardly extending flange 12 and an outwardlyextending flange 13 forming a substantial Z-secti-on. The flange 13 hasan extending portion which is bent back on itself to form on overlappingflange 14 for adding strength to the element. The adjacent portion ofthe web 11 and the flange 12 are lanced at 15 with the section 16therebetween forced inwardly into the area between the flange 12 and webto form an elongated tunnel 17. As illustrated in FIGURE 1, the sinuousspring strip 21 has oppositely disposed loops 22 and 23 joined bystraight portions 24. The endmost straight portion 25 has a reverselybent end section 26 which prevents the portion 25 from moving outwardlyof a securing tunnel or clip. Because of the large end portion 26, thetunnels 17 are elongated so that the end 26 can be moved therethroughwhen the end of the spring 25 is to be secured thereby.

As illustrated in FIGURES 1 and 2, after the end 25 is within the tunnel17, the upper portion 27 of the sections 16 is bent back into the planeof the web 11. This clamps the lower portion of the section 16 about theend section 25 of the spring strip to securely lock it in position.

The spring strip 21 illustrated in FIG. 2 is formed on an arc of smallradius which is extended into an enlarged radius when both ends of thespring strip is secured to oppositely disposed frame elements. Thisleaves the crown in the assembled spring strips and in the cushionformed thereby.

In FIG. 5 a flange 28, which is similar to the flange 12 v is slopedupwardly at an angle to force a crown in the spring strips when flat orsubstantially flat spring strips are employed across the oppositelydisposed frame element.

The frame element 10 can be secured to wood rails at opposite sides of achair and can be employed on all four sides thereof. The frame elementcan be of continuous length or separate lengths when welded or otherwisese-' cured together to form the front, rear and side rail elements ofthe seat frame. A similar construction can be employed for the frame ofa davenport or bed in which case thicker sheet material will be used forthe frame elements to withstand the greater load.

What is claimed is:

1. In combination, a plurality of sinuous spring strips, a frame elementfor supporting the ends of said sinuous spring strips, said elementhaving a web and a flange portion extending therefrom, and sectionslanced in an adjacent web and flange portion which are pushed outwardlyto form elongated tunnels between the web and flange portion, the endsof said sinuous spring strips being disposed in said tunnels.

2. A frame element for supporting the end of a sinuous spring strip,said element having a web from which flange portions extend in oppositedirections to provide a substantially Z-shaped cross section, theinwardly extending flange portion and the adjacent portion of the webhaving sections severed therefrom by pairs of lanced cuts extendingtherethrough, the severed sections being bent into the angle between theweb and flange portion to form elongated tunnels for receiving the endsof the spring strip, the ends being locked in posit-ion when a portionof the severed section is bent back substantially into the plane of theweb.

3. A frame element for supporting the end of a sinuous spring strip,said element having a web from which flange portions extend in oppositedirections to provide a sub stantially Z-shaped cross section, theinwardly extending flange portion and the adjacent portion of the webhaving sections severed therefrom by pairs of lanced cuts extendingtherethrough, the severed sections being bent into the angle between theweb and flange portion to form elongated tunnels for receiving the endsof the spring strip, the ends being locked in position when a portion ofthe severed section is bent back substantially into the plane of theweb, said inwardly extending flange sloping upwardly to form an angleless than 90 degrees with said web.

4. A frame element for supporting the end of a sinuous spring strip,said element having a web from which flange portions extend in oppositedirections to provide a substantially Z-shaped cross section, theinwardly extending flange portion and the adjacent portion of the webhaving sections severed therefrom by pairs of lanced cuts extendingtherethrough, the severed sections being bent into the angle between theweb and flange portion to form elongated 5. In combination, at least onesinuous spring strip, a frame element for supporting the end of saidsinuous spring strip, said element including a web and a flangeextending angularly away therefrom, a section lanced in adjacent web andflange portions and pushed outwardly without stretching thereof to forman elongated tunnel between said web and said flange, an end straightportion of said sinuous spring strip being disposed in said tunnel.

References Cited by the Examiner UNITED STATES PATENTS 2,427,393 9/ 1947Eckel 29-521 X 2,532,875 12/1950 Asaro 2671 10 2,657,738 11/ 1953Kruszona 5260 X 2,669,290 2/ 1954 Neely 5260 X 2,695,658 11/ 1954 Flint5260 X 2,934,133 4/ 1960 Pawlikowski 5260 2,950,486 8/1960 Heyl 5-2603,217,894 11/ 1965 Shewell 248224 X FOREIGN PATENTS 248,782 1/1964Australia.

563,624 1/ 1958 Belgium.

657,162 2/ 1938 Germany.

26,479 11/ 1910 Great Britain.

FRANK L. ABBOTT, Primary Examiner.

M. O. WARNECKE, Assistant Examiner.

1. IN COMBINATION, A PLURALITY OF SINUOUS SPRING STRIPS, A FRAME ELEMENTFOR SUPPORTING THE ENDS OF SAID SINUOUS SPRING STRIPS, SAID ELEMENTHAVING A WEB AND A FLANGE PORTION EXTENDING THEREFROM, AND SECTIONSLANCED IN AN ADJACENT WEB AND FLANGE PORTION WHICH ARE PUSHED OUTWARDLYTO FORM ELONGATED TUNNELS BETWEEN THE WEB AND FLANGE PORTION, THE ENDSOF SAID SINUOUS SPRING STRIPS BEING DISPOSED IN SAID TUNNELS.